package string;

public class StringBuilderDemo {
    public static void main(String[] args) {
/*        String str= "好好学习Java";
        //复制str的内容到Builder中--------好好学习Java
        StringBuilder  builder = new StringBuilder(str);

        //append（）； 追加内容------在末尾追加
        builder.append(",为了找个好工作");
        System.out.println(builder);

        //repalce():替换部分内容
        builder.replace(9,16,"就是为了改变世界");
        System.out.println(builder);

        //delete():删除部分内容（含头不含尾）
        builder.delete(0,8);//删除下标为0-7的
        System.out.println(builder);//就是为了改变世界

        //insert():插入内容
        builder.insert(0,"活着");
        System.out.println(builder);//活着，就是为了改变世界*/

        String str  = "好好学习";
        StringBuilder builder = new StringBuilder(str);
        builder.append(",为了找个好工作");
        System.out.println(builder);

        builder.replace(5,13,"就是为了改变世界");
        System.out.println(builder);

        builder.delete(0,5);
        System.out.println(builder);

        builder.insert(0,"活着");
        System.out.println(builder);





        /*//String的创建方式：
        StringBuilder builder1 = new StringBuilder();//空字符串
        StringBuilder builder2 = new StringBuilder("abc");//abc串

        //String和StringBuilder互转
        String str = "abc";
        StringBuilder builder3 = new StringBuilder(str);//abc串
        String str2 = builder3.toString();*/

        /*//String的创建方式：
        StringBuilder builder1 =new StringBuilder();
        StringBuilder builder2 = new StringBuilder("abc");

        //huazhuan
        String str = "abc";
        StringBuilder builder3= new StringBuilder(str);
        String str2= builder3.toString();*/








    }
}

